


Act Your Age

by ectothermal



Series: baby teeth [1]
Category: Supernatural, Teen Wolf (TV)
Genre: Childhood Sexual Abuse, First Time Blow Jobs, I'm Sorry, M/M, Sibling Incest, Stiles Stilinski is a Winchester, i mean... they're all children, non-con warning used because stiles is a child, stiles is 11 sam is 15 dean is 19
Language: English
Status: Completed
Published: 2018-05-30
Updated: 2018-05-30
Packaged: 2019-05-15 22:28:12
Rating: Explicit
Warnings: Rape/Non-Con, Underage
Chapters: 1
Words: 1,463
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14799161
Author URL: https://archiveofourown.org/users/ectothermal/pseuds/ectothermal
Summary: Stiles isn’t anybody’s good boy.It makes sense; he knows he’s loud and annoying and can’t sit still. He sees the exhaustion on Daddy’s face when he tells him to settle down, over and over again. He knows Sam doesn’t get enough sleep because he gets stuck sharing beds with him. Still - it stings, just a little. He tries to be good.





	Act Your Age

**Author's Note:**

> tumblr prompt fill from [kermiethefrog](https://archiveofourown.org/users/kermiethefrog/pseuds/kermiethefrog):
> 
> "sam winchester/stiles stilinski, but that au where they are brothers ya fuckin feel, underage because i'm nasty and idgaf anymore"
> 
> boy..................... idgaf anymore either amen

“Come on, Stiles, you’re not a baby anymore. Act your age,” Daddy murmurs, pulling Stiles’ fingers out of his mouth. Stiles glances sideways at Sam as he wipes his fingers off on his pants, and Sam’s face twists in sympathy; he pats the back of Stiles’ neck with a big, heavy hand as Stiles starts to chew on the cuff of his sweater. They watch Daddy check and pack his weapons, methodical, while Dean loads spare magazines at the little motel room’s table in the corner. When he’s done, he gathers them up between his hands to dump them alongside the guns.

“Dean, you’re with me tonight. Let’s go,” says Daddy, zipping up the duffel and grunting heavily as he swings it onto his shoulder. Dean’s brows shoot up and then furrow in the next moment, concern taking over his surprise.

“Whoa, Dad, hang on, I can’t go - who’s gonna watch the boys?” Stiles doesn’t know where Daddy and Dean are going tonight, but he knows what Dean sounds like when he’s nervous, when he’s scared, and it sinks anxiety into Stiles’ stomach. Sam squeezes the back of his neck.

“Sam can handle it. He’s older than you were when you started watching them, anyway,” Daddy says, both of his big hands on Dean’s shoulders, squeezing hard, as if he could work the fear out of Dean like that. “And I need you with me on this one.”

Dean glances at Sam, and then at Stiles, before he pulls himself up from his core, jaw clenched against the fear and eyes leveled on Daddy’s. “Yes, sir.”

“Good boy.” Daddy’s voice is a low rumble as he ruffles Dean’s hair, and he pats his lower back to tell him to head outside as he turns to Sam. “You know the rules. Don’t you leave this room for anything.”

“Yes, sir,” says Sam. He doesn’t get a ‘good boy’ back, but Stiles doesn’t expect him to, and he knows Sam doesn’t either. Dean is Daddy’s good boy, and Sam is Dean’s good boy. That’s how it works.

Stiles isn’t anybody’s good boy.

It makes sense; he knows he’s loud and annoying and can’t sit still. He sees the exhaustion on Daddy’s face when he tells him to settle down, over and over again. He knows Sam doesn’t get enough sleep because he gets stuck sharing beds with him. Still - it stings, just a little. He tries to be good.

He and Sam listen in silence to the Impala’s engine as it pulls out and fades away; when even the faintest hint of it is gone, Stiles looks up at his brother - he got so tall so fast - and mumbles around his hoodie sleeve. “Are they gonna be okay?”

“Yeah,” says Sam, immediately, wrapping his arm around Stiles’ shoulders to hug him close to his side. “Yeah, of course. They always are.” He rubs Stiles’ upper arm in an attempt at comfort, but the worried slant of Stiles’ thick eyebrows doesn’t ease. “Hey, let’s watch some TV, huh?”

Stiles nods, and Sam grabs for the remote; the TV hums as it flickers to life, and Stiles pulls his sleeve out of his mouth. “Power Rangers?” He isn’t allowed to watch Power Rangers. Daddy calls it ‘fruity,’ and besides, the last time he got away with watching it he ended up kneeing himself in the face trying to do high kicks. Sam looks back down at him, and he laughs, the soft puff of breath and wide smile that he almost always saves for just Dean.

“I don’t think it’s on this late, but we can check,” he says.

It’s not, but Sam finds some made-for-TV cop movie with bad costuming and worse dialogue that holds Stiles’ interest; Stiles settles into his brother’s side, sleeve wadded up in his mouth again.

“Stiles, that’s gross, come on.” Sam’s arm comes up underneath Stiles’ to bat his hand away; Stiles barely opens his mouth to protest before Sam replaces the fabric with his own fingers. “Here,” he says, quietly. “I’m not gonna tell Dad on you.” Stiles hesitates, but nods as he settles back down, holding Sam’s hand with both of his as he sucks on his fingers.

“Good boy,” Sam murmurs.

It continues like this - Sam feeds Stiles’ oral fixation, offering his fingers whenever Daddy and Dean are gone. He starts offering them at night, too, with his broad back turned to the opposite bed so they can’t see him curled around Stiles’ small frame, can’t see Stiles drooling down thick fingers as he sleeps like a rock for once in his life. It’s like magic; even Daddy comments on how much calmer Stiles seems, tells Sam he’s doing a good job.

“Hey, Stiles,” Sam starts, late one evening - Daddy and Dean are gone again, but his voice is hushed as he nudges Stiles gently and pulls his fingers out of his mouth. “I wanna try something. That okay?”

“Umm,” says Stiles, pulling his knees up as Sam withdraws his arm from around his shoulders, “what is it?” Sam shifts down until just his shoulders are propped up against the pillows.

“It makes you feel better to have something to suck on, right?” Sam asks, reaching up to rub Stiles’ side as he makes himself comfortable; Stiles nods, brows furrowed in confusion, because Sam already knows that. “Then this’ll make us both feel good.”

Sam pops the fly of his jeans open, lifting his hips a little to shift them down with his underwear. He pulls his cock free and lets it rest on his stomach, bare where his shirt has ridden up. Stiles stares at it, eyes wide and chewing on his fingers for lack of anything else as his nerves climb; Sam takes notice fast, reaching up to smooth his hands over Stiles’ buzzed hair and turn his head to look up at his face again. “It’s okay,” he soothes, “I started doing this for Dean when I was your age.”

“Yeah?” Stiles asks, slowly drawing his fingers away from his mouth.

“Yeah,” Sam nods, smiling reassuringly. Stiles nods a little bit, too.

“And it feels good?”

“ _Really_ good. You wanna make me feel good, right, Stiles? You wanna be a good boy for me?” That’s it - the magic words. Stiles perks up, nodding fast, and Sam grins wide. “Good. C'mon, lay your head right here.” He guides Stiles by the back of his neck to lay with his head on his stomach, lifting his cock to press the tip against the seam of Stiles’ lips.

“Open up,” Sam murmurs, and Stiles does, drawing the head into his mouth and starting to suck in a gentle rhythm; he can feel Sam start to swell in his mouth, pressing further back, pushing his jaw open wider. He makes a soft noise of discomfort, and Sam starts to rub his back. He reaches for Stiles’ hand that rests curled against his hipbone and wraps his fingers around the base of his cock, covering his hand with his big one to guide him through the first few strokes.

“Just like that, okay? You’re doing so good.” Sam’s voice sounds tighter, his breath coming out in sharp pants as Stiles continues the motion Sam started for him; his stomach flexes, bobbing Stiles’ head up with the force of it, and it’s not long before his hips start to follow, drawing startled, muffled noises from Stiles. He anchors his hand on the back of Stiles’ neck, groaning low as he returns the other to guide Stiles through faster strokes.

Sam cums fast, without much warning other than a sudden low, gravelly groan, and Stiles chokes, spluttering as he jerks his head back. Sam lets him go, head sunk back into the pillows and breathing hard as Stiles coughs, spilling down his chin. The sight of it makes Sam’s spent cock twitch uncomfortably in interest, but he sits up, sliding his thumb up Stiles’ chin to push his cum back into his mouth.

“Hey, hey, it’s okay,” he says, “I did the same thing my first time, you just gotta swallow it.” Stiles nods, wiping his nose on the back of his wrist as he does what he’s told. Sam sweeps Stiles’ tears away with gentle fingers, pausing only to tuck himself back into his underwear before he wraps his arms around his little brother, pulling him onto his chest into a tight hug. “Good job, baby brother,” he says, muffled against Stiles’ hair. Stiles grabs for his wrist, and Sam lets him take it, leans back to watch him suck on his fingers again. “You’re my good boy, huh?”

Stiles nods. Dean is Daddy’s good boy, Sam is Dean’s good boy, and Stiles is Sam’s good boy.

That’s how it works.


End file.
